standard constrain： 1. persons with full capacity for civil conduct aged ≥60 years; 2. subjects voluntarily agree to participate in the research and sign an informed consent form, and can provide valid identification; understand and comply with the requirements of the trial protocol; have the ability to understand (non-illiterate) research procedures and participate in the planned follow-up; 3. axillary body temperature \<37.3℃; 4. female subjects and male subjects of childbearing age agree to take effective contraceptive measures during the study period. exclusion criteria： 1. the results of physical examination and laboratory examination before screening are abnormal and clinically significant as judged by clinicians, or systolic blood pressure ≥160mmhg and/or diastolic blood pressure ≥100mmhg before screening; 2. a history of severe allergies to any component of the test vaccine, including aluminum preparations, such as: anaphylactic shock, allergic laryngeal edema, allergic purpura, thrombocytopenic purpura, local allergic necrosis (arthus reaction), dyspnea, blood vessels neuroedema, etc.; or any previous history of serious side effects after the use of any vaccine or drug; 3. people with a history of sars and sars-cov-2 (meet any of the following: ①have a history of sars and sars-cov-2 infection or onset; ②during this sras-cov-2 epidemic, there are patients who have been diagnosed with the new crown/ suspected patient contact history); 4. have taken antipyretic or analgesic within 24 hours before the first dose of vaccination; 5. inoculate subunit vaccine and/or inactivated vaccine within 14 days before the first dose of vaccine, and inoculate live attenuated vaccine within 30 days; 6. people suffering from the following diseases: * acute (within 72 hours) feverish illness; * suffering from digestive system diseases (such as diarrhea, abdominal pain, vomiting, etc.) in the past 7 days; * suffering from congenital malformations or developmental disorders, genetic defects, severe malnutrition, etc.; * congenital or acquired immunodeficiency or autoimmune disease history or receiving immunomodulator treatment within 6 months, such as hormones; or monoclonal antibodies; or thymosin; or interferon, etc.; but local medication (such as ointment, eye drops, inhalation or nasal spray); * known to have been diagnosed with infectious diseases, such as: tuberculosis, viral hepatitis and/or human immunodeficiency virus hiv antibody positive or syphilis specific antibody positive; * neurological diseases or neurodevelopmental dysfunction (for example, migraine, epilepsy, stroke, seizures in the last three years, encephalopathy, focal neurological deficits, guillain-barré syndrome, encephalomyelitis or transverse myelitis; history of mental illness or family history; ⑦functional asplenia, as well as any cause of aspleen or splenectomy; ⑧severe chronic diseases or conditions that cannot be controlled smoothly in the advanced stage, such as diabetes and thyroid disease; ⑨severe liver and kidney diseases; respiratory diseases that currently require daily drug treatment (for example, chronic obstructive pulmonary disease \[copd\], asthma) or any treatment for exacerbation of respiratory diseases (for example, asthma exacerbation) in the last 5 years; suffering from severe history of cardiovascular disease (such as congestive heart failure, cardiomyopathy, ischemic heart disease, arrhythmia, conduction block, myocardial infarction, pulmonary heart disease) or myocarditis or pericarditis; ⑩have thrombocytopenia, any coagulation dysfunction or receive anticoagulant treatment, etc.; ?tumor patients; 7. have received blood or blood-related products, including immunoglobulin, within 3 months; or plan to use it during the research period; 8. those who are already pregnant (including a positive urine pregnancy test), or are breastfeeding; 9. any research or unregistered products (drugs, vaccines, biological products or devices) other than research products have been used within 3 months, or planned to be used during the research period; 10. the investigator believes that any disease or condition in the subject may put the subject at an unacceptable risk; the subject cannot meet the requirements of the protocol; it interferes with the assessment of the vaccine response.

standard constrain： 1. persons with full capacity for civil conduct aged ≥60 years; 2. subjects voluntarily agree to participate in the research and sign an informed consent form, and can provide valid identification; understand and comply with the requirements of the trial protocol; have the ability to understand (non-illiterate) research procedures and participate in the planned follow-up; 3. axillary body temperature \<37.3℃; 4. female subjects and male subjects of childbearing age agree to take effective contraceptive measures during the study period. exclusion criteria： 1. the results of physical examination and laboratory examination before screening are abnormal and clinically significant as judged by clinicians, or systolic blood pressure ≥160mmhg and/or diastolic blood pressure ≥100mmhg before screening; 2. a history of severe allergies to any component of the test vaccine, including aluminum preparations, such as: anaphylactic shock, allergic laryngeal edema, allergic purpura, thrombocytopenic purpura, local allergic necrosis (arthus reaction), dyspnea, blood vessels neuroedema, etc.; or any previous history of serious side effects after the use of any vaccine or drug; 3. people with a history of sars and sars-cov-2 (meet any of the following: ①have a history of sars and sars-cov-2 infection or onset; ②during this sras-cov-2 epidemic, there are patients who have been diagnosed with the new crown/ suspected patient contact history); 4. have taken antipyretic or analgesic within 24 hours before the first dose of vaccination; 5. inoculate subunit vaccine and/or inactivated vaccine within 14 days before the first dose of vaccine, and inoculate live attenuated vaccine within 30 days; 6. people suffering from the following diseases: * acute (within 72 hours) feverish illness; * suffering from digestive system diseases (such as diarrhea, abdominal pain, vomiting, etc.) in the past 7 days; * suffering from congenital malformations or developmental disorders, genetic defects, severe malnutrition, etc.; * congenital or acquired immunodeficiency or autoimmune disease history or receiving immunomodulator treatment within 6 months, such as hormones; or monoclonal antibodies; or thymosin; or interferon, etc.; but local medication (such as ointment, eye drops, inhalation or nasal spray); * known to have been diagnosed with infectious diseases, such as: tuberculosis, viral hepatitis and/or human immunodeficiency virus hiv antibody positive or syphilis specific antibody positive; * neurological diseases or neurodevelopmental dysfunction (for example, migraine, epilepsy, stroke, seizures in the last three years, encephalopathy, focal neurological deficits, guillain-barré syndrome, encephalomyelitis or transverse myelitis; history of mental illness or family history; ⑦functional asplenia, as well as any cause of aspleen or splenectomy; ⑧severe chronic diseases or conditions that cannot be controlled smoothly in the advanced stage, such as diabetes and thyroid disease; ⑨severe liver and kidney diseases; respiratory diseases that currently require daily drug treatment (for example, chronic obstructive pulmonary disease \[copd\], asthma) or any treatment for exacerbation of respiratory diseases (for example, asthma exacerbation) in the last 5 years; suffering from severe history of cardiovascular disease (such as congestive heart failure, cardiomyopathy, ischemic heart disease, arrhythmia, conduction block, myocardial infarction, pulmonary heart disease) or myocarditis or pericarditis; ⑩have thrombocytopenia, any coagulation dysfunction or receive anticoagulant treatment, etc.; ?tumor patients; 7. have received blood or blood-related products, including immunoglobulin, within 3 months; or plan to use it during the research period; 8. those who are already pregnant (including a positive urine pregnancy test), or are breastfeeding; 9. any research or unregistered products (drugs, vaccines, biological products or devices) other than research products have been used within 3 months, or planned to be used during the research period; 10. the investigator believes that any disease or condition in the subject may put the subject at an unacceptable risk; the subject cannot meet the requirements of the protocol; it interferes with the assessment of the vaccine response.

standard constrain： persons with full capacity for civil conduct aged ≥60 years; subjects voluntarily agree to participate in the research and sign an informed consent form, and can provide valid identification; understand and comply with the requirements of the trial protocol; have the ability to understand (non-illiterate) research procedures and participate in the planned follow-up; axillary body temperature <37.3℃; female subjects and male subjects of childbearing age agree to take effective contraceptive measures during the study period. exclusion criteria： the results of physical examination and laboratory examination before screening are abnormal and clinically significant as judged by clinicians, or systolic blood pressure ≥160mmhg and/or diastolic blood pressure ≥100mmhg before screening; a history of severe allergies to any component of the test vaccine, including aluminum preparations, such as: anaphylactic shock, allergic laryngeal edema, allergic purpura, thrombocytopenic purpura, local allergic necrosis (arthus reaction), dyspnea, blood vessels neuroedema, etc.; or any previous history of serious side effects after the use of any vaccine or drug; people with a history of sars and sars-cov-2 (meet any of the following: ①have a history of sars and sars-cov-2 infection or onset; ②during this sras-cov-2 epidemic, there are patients who have been diagnosed with the new crown/ suspected patient contact history); have taken antipyretic or analgesic within 24 hours before the first dose of vaccination; inoculate subunit vaccine and/or inactivated vaccine within 14 days before the first dose of vaccine, and inoculate live attenuated vaccine within 30 days; people suffering from the following diseases: acute (within 72 hours) feverish illness; suffering from digestive system diseases (such as diarrhea, abdominal pain, vomiting, etc.) in the past 7 days; suffering from congenital malformations or developmental disorders, genetic defects, severe malnutrition, etc.; congenital or acquired immunodeficiency or autoimmune disease history or receiving immunomodulator treatment within 6 months, such as hormones; or monoclonal antibodies; or thymosin; or interferon, etc.; but local medication (such as ointment, eye drops, inhalation or nasal spray); known to have been diagnosed with infectious diseases, such as: tuberculosis, viral hepatitis and/or human immunodeficiency virus hiv antibody positive or syphilis specific antibody positive; neurological diseases or neurodevelopmental dysfunction (for example, migraine, epilepsy, stroke, seizures in the last three years, encephalopathy, focal neurological deficits, guillain-barré syndrome, encephalomyelitis or transverse myelitis; history of mental illness or family history; ⑦functional asplenia, as well as any cause of aspleen or splenectomy; ⑧severe chronic diseases or conditions that cannot be controlled smoothly in the advanced stage, such as diabetes and thyroid disease; ⑨severe liver and kidney diseases; respiratory diseases that currently require daily drug treatment (for example, chronic obstructive pulmonary disease [copd], asthma) or any treatment for exacerbation of respiratory diseases (for example, asthma exacerbation) in the last 5 years; suffering from severe history of cardiovascular disease (such as congestive heart failure, cardiomyopathy, ischemic heart disease, arrhythmia, conduction block, myocardial infarction, pulmonary heart disease) or myocarditis or pericarditis; ⑩have thrombocytopenia, any coagulation dysfunction or receive anticoagulant treatment, etc.; ?tumor patients; have received blood or blood-related products, including immunoglobulin, within 3 months; or plan to use it during the research period; those who are already pregnant (including a positive urine pregnancy test), or are breastfeeding; any research or unregistered products (drugs, vaccines, biological products or devices) other than research products have been used within 3 months, or planned to be used during the research period; the investigator believes that any disease or condition in the subject may put the subject at an unacceptable risk; the subject cannot meet the requirements of the protocol; it interferes with the assessment of the vaccine response.

standard constrain： persons with full capacity for civil conduct aged ≥60 years; subjects voluntarily agree to participate in the research and sign an informed consent form, and can provide valid identification; understand and comply with the requirements of the trial protocol; have the ability to understand (non-illiterate) research procedures and participate in the planned follow-up; axillary body temperature <37.3℃; female subjects and male subjects of childbearing age agree to take effective contraceptive measures during the study period. exclusion criteria： the results of physical examination and laboratory examination before screening are abnormal and clinically significant as judged by clinicians, or systolic blood pressure ≥160mmhg and/or diastolic blood pressure ≥100mmhg before screening; a history of severe allergies to any component of the test vaccine, including aluminum preparations, such as: anaphylactic shock, allergic laryngeal edema, allergic purpura, thrombocytopenic purpura, local allergic necrosis (arthus reaction), dyspnea, blood vessels neuroedema, etc.; or any previous history of serious side effects after the use of any vaccine or drug; people with a history of sars and sars-cov-2 (meet any of the following: ①have a history of sars and sars-cov-2 infection or onset; ②during this sras-cov-2 epidemic, there are patients who have been diagnosed with the new crown/ suspected patient contact history); have taken antipyretic or analgesic within 24 hours before the first dose of vaccination; inoculate subunit vaccine and/or inactivated vaccine within 14 days before the first dose of vaccine, and inoculate live attenuated vaccine within 30 days; people suffering from the following diseases: acute (within 72 hours) feverish illness; suffering from digestive system diseases (such as diarrhea, abdominal pain, vomiting, etc.) in the past 7 days; suffering from congenital malformations or developmental disorders, genetic defects, severe malnutrition, etc.; congenital or acquired immunodeficiency or autoimmune disease history or receiving immunomodulator treatment within 6 months, such as hormones; or monoclonal antibodies; or thymosin; or interferon, etc.; but local medication (such as ointment, eye drops, inhalation or nasal spray); known to have been diagnosed with infectious diseases, such as: tuberculosis, viral hepatitis and/or human immunodeficiency virus hiv antibody positive or syphilis specific antibody positive; neurological diseases or neurodevelopmental dysfunction (for example, migraine, epilepsy, stroke, seizures in the last three years, encephalopathy, focal neurological deficits, guillain-barré syndrome, encephalomyelitis or transverse myelitis; history of mental illness or family history; ⑦functional asplenia, as well as any cause of aspleen or splenectomy; ⑧severe chronic diseases or conditions that cannot be controlled smoothly in the advanced stage, such as diabetes and thyroid disease; ⑨severe liver and kidney diseases; respiratory diseases that currently require daily drug treatment (for example, chronic obstructive pulmonary disease [copd], asthma) or any treatment for exacerbation of respiratory diseases (for example, asthma exacerbation) in the last 5 years; suffering from severe history of cardiovascular disease (such as congestive heart failure, cardiomyopathy, ischemic heart disease, arrhythmia, conduction block, myocardial infarction, pulmonary heart disease) or myocarditis or pericarditis; ⑩have thrombocytopenia, any coagulation dysfunction or receive anticoagulant treatment, etc.; ?tumor patients; have received blood or blood-related products, including immunoglobulin, within 3 months; or plan to use it during the research period; those who are already pregnant (including a positive urine pregnancy test), or are breastfeeding; any research or unregistered products (drugs, vaccines, biological products or devices) other than research products have been used within 3 months, or planned to be used during the research period; the investigator believes that any disease or condition in the subject may put the subject at an unacceptable risk; the subject cannot meet the requirements of the protocol; it interferes with the assessment of the vaccine response.

standard constrain： 1. persons with full capacity for civil conduct aged ≥60 years; 2. subjects voluntarily agree to participate in the research and sign an informed consent form, and can provide valid identification; understand and comply with the requirements of the trial protocol; have the ability to understand (non-illiterate) research procedures and participate in the planned follow-up; 3. axillary body temperature <37.3℃; 4. female subjects and male subjects of childbearing age agree to take effective contraceptive measures during the study period. exclusion criteria： 1. the results of physical examination and laboratory examination before screening are abnormal and clinically significant as judged by clinicians, or systolic blood pressure ≥160mmhg and/or diastolic blood pressure ≥100mmhg before screening; 2. a history of severe allergies to any component of the test vaccine, including aluminum preparations, such as: anaphylactic shock, allergic laryngeal edema, allergic purpura, thrombocytopenic purpura, local allergic necrosis (arthus reaction), dyspnea, blood vessels neuroedema, etc.; or any previous history of serious side effects after the use of any vaccine or drug; 3. people with a history of sars and sars-cov-2 (meet any of the following: ①have a history of sars and sars-cov-2 infection or onset; ②during this sras-cov-2 epidemic, there are patients who have been diagnosed with the new crown/ suspected patient contact history); 4. have taken antipyretic or analgesic within 24 hours before the first dose of vaccination; 5. inoculate subunit vaccine and/or inactivated vaccine within 14 days before the first dose of vaccine, and inoculate live attenuated vaccine within 30 days; 6. people suffering from the following diseases: - acute (within 72 hours) feverish illness; - suffering from digestive system diseases (such as diarrhea, abdominal pain, vomiting, etc.) in the past 7 days; - suffering from congenital malformations or developmental disorders, genetic defects, severe malnutrition, etc.; - congenital or acquired immunodeficiency or autoimmune disease history or receiving immunomodulator treatment within 6 months, such as hormones; or monoclonal antibodies; or thymosin; or interferon, etc.; but local medication (such as ointment, eye drops, inhalation or nasal spray); - known to have been diagnosed with infectious diseases, such as: tuberculosis, viral hepatitis and/or human immunodeficiency virus hiv antibody positive or syphilis specific antibody positive; - neurological diseases or neurodevelopmental dysfunction (for example, migraine, epilepsy, stroke, seizures in the last three years, encephalopathy, focal neurological deficits, guillain-barré syndrome, encephalomyelitis or transverse myelitis; history of mental illness or family history; ⑦functional asplenia, as well as any cause of aspleen or splenectomy; ⑧severe chronic diseases or conditions that cannot be controlled smoothly in the advanced stage, such as diabetes and thyroid disease; ⑨severe liver and kidney diseases; respiratory diseases that currently require daily drug treatment (for example, chronic obstructive pulmonary disease [copd], asthma) or any treatment for exacerbation of respiratory diseases (for example, asthma exacerbation) in the last 5 years; suffering from severe history of cardiovascular disease (such as congestive heart failure, cardiomyopathy, ischemic heart disease, arrhythmia, conduction block, myocardial infarction, pulmonary heart disease) or myocarditis or pericarditis; ⑩have thrombocytopenia, any coagulation dysfunction or receive anticoagulant treatment, etc.; ?tumor patients; 7. have received blood or blood-related products, including immunoglobulin, within 3 months; or plan to use it during the research period; 8. those who are already pregnant (including a positive urine pregnancy test), or are breastfeeding; 9. any research or unregistered products (drugs, vaccines, biological products or devices) other than research products have been used within 3 months, or planned to be used during the research period; 10. the investigator believes that any disease or condition in the subject may put the subject at an unacceptable risk; the subject cannot meet the requirements of the protocol; it interferes with the assessment of the vaccine response.

standard constrain： 1. persons with full capacity for civil conduct aged ≥60 years; 2. subjects voluntarily agree to participate in the research and sign an informed consent form, and can provide valid identification; understand and comply with the requirements of the trial protocol; have the ability to understand (non-illiterate) research procedures and participate in the planned follow-up; 3. axillary body temperature <37.3℃; 4. female subjects and male subjects of childbearing age agree to take effective contraceptive measures during the study period. exclusion criteria： 1. the results of physical examination and laboratory examination before screening are abnormal and clinically significant as judged by clinicians, or systolic blood pressure ≥160mmhg and/or diastolic blood pressure ≥100mmhg before screening; 2. a history of severe allergies to any component of the test vaccine, including aluminum preparations, such as: anaphylactic shock, allergic laryngeal edema, allergic purpura, thrombocytopenic purpura, local allergic necrosis (arthus reaction), dyspnea, blood vessels neuroedema, etc.; or any previous history of serious side effects after the use of any vaccine or drug; 3. people with a history of sars and sars-cov-2 (meet any of the following: ①have a history of sars and sars-cov-2 infection or onset; ②during this sras-cov-2 epidemic, there are patients who have been diagnosed with the new crown/ suspected patient contact history); 4. have taken antipyretic or analgesic within 24 hours before the first dose of vaccination; 5. inoculate subunit vaccine and/or inactivated vaccine within 14 days before the first dose of vaccine, and inoculate live attenuated vaccine within 30 days; 6. people suffering from the following diseases: - acute (within 72 hours) feverish illness; - suffering from digestive system diseases (such as diarrhea, abdominal pain, vomiting, etc.) in the past 7 days; - suffering from congenital malformations or developmental disorders, genetic defects, severe malnutrition, etc.; - congenital or acquired immunodeficiency or autoimmune disease history or receiving immunomodulator treatment within 6 months, such as hormones; or monoclonal antibodies; or thymosin; or interferon, etc.; but local medication (such as ointment, eye drops, inhalation or nasal spray); - known to have been diagnosed with infectious diseases, such as: tuberculosis, viral hepatitis and/or human immunodeficiency virus hiv antibody positive or syphilis specific antibody positive; - neurological diseases or neurodevelopmental dysfunction (for example, migraine, epilepsy, stroke, seizures in the last three years, encephalopathy, focal neurological deficits, guillain-barré syndrome, encephalomyelitis or transverse myelitis; history of mental illness or family history; ⑦functional asplenia, as well as any cause of aspleen or splenectomy; ⑧severe chronic diseases or conditions that cannot be controlled smoothly in the advanced stage, such as diabetes and thyroid disease; ⑨severe liver and kidney diseases; respiratory diseases that currently require daily drug treatment (for example, chronic obstructive pulmonary disease [copd], asthma) or any treatment for exacerbation of respiratory diseases (for example, asthma exacerbation) in the last 5 years; suffering from severe history of cardiovascular disease (such as congestive heart failure, cardiomyopathy, ischemic heart disease, arrhythmia, conduction block, myocardial infarction, pulmonary heart disease) or myocarditis or pericarditis; ⑩have thrombocytopenia, any coagulation dysfunction or receive anticoagulant treatment, etc.; ?tumor patients; 7. have received blood or blood-related products, including immunoglobulin, within 3 months; or plan to use it during the research period; 8. those who are already pregnant (including a positive urine pregnancy test), or are breastfeeding; 9. any research or unregistered products (drugs, vaccines, biological products or devices) other than research products have been used within 3 months, or planned to be used during the research period; 10. the investigator believes that any disease or condition in the subject may put the subject at an unacceptable risk; the subject cannot meet the requirements of the protocol; it interferes with the assessment of the vaccine response.